全文获取类型
收费全文 | 96篇 |
免费 | 4篇 |
专业分类
林业 | 9篇 |
农学 | 1篇 |
基础科学 | 1篇 |
19篇 | |
综合类 | 15篇 |
畜牧兽医 | 54篇 |
植物保护 | 1篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 10篇 |
2011年 | 4篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 6篇 |
2007年 | 5篇 |
2006年 | 12篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1993年 | 1篇 |
1934年 | 1篇 |
排序方式: 共有100条查询结果,搜索用时 15 毫秒
1.
Dr Uwe Schindler Joerg Steidl Lothar Mueller 《Archives of Agronomy and Soil Science》2013,59(1):63-73
Abstract The influence of regional soil distribution and land use on discharge formation in the “Stettiner Haff” catchment (8,456 km2) was investigated. The model ABIMO was used to calculate mean discharge for a long period (1961 – 1990) in consideration of regional differences in hydrological site conditions and soil heterogeneity. The highest discharge was found on settlement areas (276 mm a?1), on devastated plots (319 mm a?1) and on the non-hydromorphic agriculturally used sandy soils (214 mm a?1). Due to their small size these sub-areas were found to influence regional discharge for a limited extent only. On loam and clay soils only about 100 mm a?1 of discharge was formed. However, this share proved to be most important for the height of regional discharge because of the high area proportion in the region. Mineral soils of comparable parent material produce lower discharge under hydromorphic conditions than under non-hydromorphic conditions. With increasing clay content of the soils these differences decreased. The agriculturally used areas were found to be most important for the region's water discharge. They accounted for 83% of the discharge, i.e. they originated 119 mm a?1 on average. At forest sites, the discharge height was about 52 mm a?1. Sites close to groundwater table (groundwater level <1 m) proved to act as depletive areas. 相似文献
2.
Anne Fischer Anne Liljander Heike Kaspar Cecilia Muriuki Hans-Henrik Fuxelius Erik Bongcam-Rudloff Etienne P de Villiers Charlotte A Huber Joachim Frey Claudia Daubenberger Richard Bishop Mario Younan Joerg Jores 《Veterinary research》2013,44(1):86
Camels are the most valuable livestock species in the Horn of Africa and play a pivotal role in the nutritional sustainability for millions of people. Their health status is therefore of utmost importance for the people living in this region. Streptococcus agalactiae, a Group B Streptococcus (GBS), is an important camel pathogen. Here we present the first epidemiological study based on genetic and phenotypic data from African camel derived GBS. Ninety-two GBS were characterized using multilocus sequence typing (MLST), capsular polysaccharide typing and in vitro antimicrobial susceptibility testing. We analysed the GBS using Bayesian linkage, phylogenetic and minimum spanning tree analyses and compared them with human GBS from East Africa in order to investigate the level of genetic exchange between GBS populations in the region. Camel GBS sequence types (STs) were distinct from other STs reported so far. We mapped specific STs and capsular types to major disease complexes caused by GBS. Widespread resistance (34%) to tetracycline was associated with acquisition of the tetM gene that is carried on a Tn916-like element, and observed primarily among GBS isolated from mastitis. The presence of tetM within different MLST clades suggests acquisition on multiple occasions. Wound infections and mastitis in camels associated with GBS are widespread and should ideally be treated with antimicrobials other than tetracycline in East Africa. 相似文献
3.
Kemner KM Kelly SD Lai B Maser J O'loughlin EJ Sholto-Douglas D Cai Z Schneegurt MA Kulpa CF Nealson KH 《Science (New York, N.Y.)》2004,306(5696):686-687
High-energy x-ray fluorescence measurements were used to make elemental maps and qualitative chemical analyses of individual Pseudomonas fluorescens strain NCIMB 11764 cells. Marked differences between planktonic and adhered cells were seen in the morphology, elemental composition, and sensitivity to Cr(VI) of hydrated cells at spatial scales of 150 nm. This technology can be applied to natural geomicrobiological systems. 相似文献
4.
Pacemaker implantation in a ferret (Mustela putorius furo) with third-degree atrioventricular block.
David Sanchez-Migallon Guzman Joerg Mayer Raffaele Melidone Robert J McCarthy Emily McCobb Anoop Kavirayani John E Rush 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):677-687
A 7.5-year-old castrated male ferret (Mustela putorius furo) was diagnosed with third-degree atrioventricular (AV) block. A monopolar epicardial pacemaker system was implanted, resulting in a regular, paced cardiac rhythm with third-degree AV block at 140 beats per minute. Over the next 2 months, the ferret developed anorexia, interstitial pneumonia, intermittent diarrhea, and hind-limb weakness and had a slow and progressive recovery. The ferret developed clinical signs of congestive heart failure 4 months after the surgery, resulting in its death 3 weeks later. Necropsy results attributed the death to cardiac failure due to extensive myocardial mineralization. To the authors' knowledge this is the first published report of surgical report of surgical pacemaker implantation in a ferret. 相似文献
5.
Isabelle Brodard Maher Alsaaod Corinne Gurtner Joerg Jores Adrian Steiner Peter Kuhnert 《Journal of veterinary diagnostic investigation》2021,33(4):801
Digital dermatitis (DD) is a major infectious foot disease of cattle worldwide. Some DD stages are associated with lameness, and the disease has significant economic and animal welfare consequences. The pathogenesis of the disease is not yet fully understood, but Treponema spp. have been associated consistently with clinical cases. Isolation of these fastidious bacteria is difficult and cumbersome. We describe an improved method enabling the culturing of the 3 Treponema spp. (T. pedis, T. phagedenis, and T. medium) from bovine foot specimens derived from DD lesions, using a combination of membrane filtering and subsequent growth on selective agar media. The entire procedure from sampling to verification of individual Treponema spp. takes up to 24 d. In addition, we established a MALDI-TOF MS–based identification method to be applied for confirmation of the different Treponema spp. This scheme provides an unambiguous, simple, and straightforward identification procedure for DD-associated Treponema spp. 相似文献
6.
7.
Chen Z Appenzeller J Lin YM Sippel-Oakley J Rinzler AG Tang J Wind SJ Solomon PM Avouris P 《Science (New York, N.Y.)》2006,311(5768):1735
Single-walled carbon nanotubes (SWCNTs) have been shown to exhibit excellent electrical properties, such as ballistic transport over several hundred nanometers at room temperature. Field-effect transistors (FETs) made from individual tubes show dc performance specifications rivaling those of state-of-the-art silicon devices. An important next step is the fabrication of integrated circuits on SWCNTs to study the high-frequency ac capabilities of SWCNTs. We built a five-stage ring oscillator that comprises, in total, 12 FETs side by side along the length of an individual carbon nanotube. A complementary metal-oxide semiconductor-type architecture was achieved by adjusting the gate work functions of the individual p-type and n-type FETs used. 相似文献
8.
El-Warrak AO Olmstead M Apelt D Deiss F Noetzli H Zlinsky K Hilbe M Bertschar-Wolfsberger R Johnson AL Auer J von Rechenberg B 《Veterinary surgery : VS》2004,33(5):495-504
OBJECTIVE: To create a model in sheep for investigation of early changes related to the formation of an interface membrane in hip prosthesis. STUDY DESIGN: Experimental study. ANIMALS: Twenty-four female adult Swiss Alpine sheep. METHODS: Sheep were divided into 2 groups of 12 for unilateral cemented total hip arthroplasty. In Group I, the prosthesis was fixed with retrograde cement gun injection to achieve a complete cement mantle, whereas in Group II a primary cement mantle defect was produced. Groups I and II were further divided into 2 sub-groups with study end points of 2 and 8.5 months after surgery. Radiographs were evaluated postoperatively and at euthanasia for migration of the femoral component and bone resorption. Histologic sections were evaluated semiquantitatively for changes in cell types and numbers, and bone reactions; and quantitatively for size of interface membrane and new bone formation. RESULTS: Radiographically, there tended to be an increase in bone resorption and periosteal bone formation throughout the femoral shaft in Group II compared with Group I, but this was only statistically significant at the region of the femoral neck (R5) at both time periods (P<.05). Semiquantitative histologic evaluation revealed significant increases (P<.05) in cellularity, numbers of fibroblasts, giant cells, macrophages, and mononuclear cells, in Group II primarily at 2 months after surgery. This was also true for interface membrane formation and bone remodeling. Quantitative data showed an increased in the size of the interface membrane and area of bone formation at 8.5 months in Group II. CONCLUSIONS: The cement defect model offered controlled and repeatable production of an interface membrane. The results suggest that a primary cement mantle defect could be a possible trigger for implant instability, eliciting a cascade of biomechanical and molecular events in bone tissue leading to aseptic loosening. CLINICAL RELEVANCE: The results show the effect of defects in the cement mantle in promoting interface membrane formation. Long-term and biochemical studies are required to evaluate the relevance of this interface membrane formation. 相似文献
9.
10.